Effect of Functional Bread Rich in Potassium, γ-Aminobutyric Acid and Angiotensin-Converting Enzyme Inhibitors on Blood Pressure, Glucose Metabolism and Endothelial Function: A Double-blind Randomized Crossover Clinical Trial

Contributions of Gamma-Aminobutyric Acid (GABA) Produced by Lactic Acid Bacteria on Food Quality and Human Health: Current Applications and Future Prospects

The need to increase food safety and improve human health has led to a worldwide increase in interest in gamma-aminobutyric acid (GABA), produced by lactic acid bacteria (LABs). GABA, produced from glutamic acid in a reaction catalyzed by glutamate decarboxylase (GAD), is a four-carbon, non-protein amino acid that is increasingly used in the food industry to improve the safety/quality of foods. In addition to the possible positive effects of GABA, called a postbiotic, on neuroprotection, improving sleep quality, alleviating depression and relieving pain, the various health benefits of GABA-enriched foods such as antidiabetic, antihypertension, and anti-inflammatory effects are also being investigated. For all these reasons, it is not surprising that efforts to identify LAB strains with a high GABA productivity and to increase GABA production from LABs through genetic engineering to increase GABA yield are accelerating. However, GABA's contributions to food safety/quality and human health have not yet been fully discussed in the literature. Therefore, this current review highlights the synthesis and food applications of GABA produced from LABs, discusses its health benefits such as, for example, alleviating drug withdrawal syndromes and regulating obesity and overeating. Still, other potential food and drug interactions (among others) remain unanswered questions to be elucidated in the future. Hence, this review paves the way toward further studies.

Effects of low-sodium bread on dietary compliance and fecal cultivable bacteria in a randomized controlled pilot trial in hypertensive subjects

High salt intake and compliance to low-sodium (LS) diets are critical in hypertension. Salt reduction in processed foods can help to achieve the target sodium intake. To verify the hypothesis that an innovative LS formulation of a traditional bread could result in a reduction of sodium intake and blood pressure, we performed a 6-month randomized controlled pilot trial on hypertensive patients. We additionally explored the effects of sodium restriction on blood pressure and fecal cultivable bacteria.Fifty-seven patients were randomized in three groups. Group A (n = 19) followed a free diet using standard bread (750 mg Na/100 g), group B (n = 18) followed a LS diet (2300 mg Na/die) using standard bread, group C (n = 20) followed a LS diet (2300 mg Na/die) using LS bread (280 mg Na/100 g). We measured 24-h urinary sodium, blood pressure, routine parameters, fecal microbial counts (26 patients).After 6 months, as compared to group A, group C showed a reduction of 24-h urinary sodium excretion (-908 mg/24 h), diastolic pressure (-9 mmHg) and microbial counts of Bacteroides, Porphyromonas, Prevotella, Enterobacteriaceae, Staphylococcus, Micrococcus. These results suggest that LS bread could increase the adherence to a LS diet, reducing sodium excretion, diastolic pressure and abundance of some fecal cultivable bacteria.Trial registration Registration nr. NCT03127553, on 25/04/2017.

Unraveling Compositional Study, Chemometric Analysis, and Cell-Based Antioxidant Potential of Selective High Nutraceutical Value Amaranth Cultivars Using a GC-MS and NMR-Based Metabolomics Approach

Amaranthus (family Amaranthaceae) is a potentially nutritious pseudocereal also known as a functional food owing to its high nutritional quality grains especially rich in essential amino acids. Emerging study, however, unambiguously indicates that apart from essential nutrients like protein, other phytochemicals present in amaranth seeds provide excellent health benefits. Squalene is one such phytonutrient found in Amaranthus seeds, which is also its largest vegetal source. In this research work, GC-MS and NMR spectroscopy-based metabolomics have been utilized for the compositional analysis of Amaranthus seeds coupled with a multivariate data set. Investigation of nonpolar and polar seed extracts of six different cultivars of amaranth identified 47 primary and secondary metabolites. One-way ANOVA showed significant quantitative metabolic variations in different cultivars of amaranth. Multivariate principal component analysis of both the GC-MS and NMR analyzed data broadly classified in two groups showed significant variations in the polar (lysine, arginine, GABA, and myoinositol) and nonpolar (squalene, tryptophan, and alkylated phenols, which are potential nutraceutical agents) metabolites. The squalene content estimated using HPLC varied significantly (1.61 to 4.72 mg g-1 seed dry weight) among six different cultivars. Positive correlations were found among the cellular antioxidant activity and squalene content. Cultivar AM-3 having the maximum squalene content showed the highest antioxidant activity evaluated on the cellular level over human embryonic kidney cells, clearly revealing potent intercellular reactive oxygen species scavenging capacity and strong membrane lipid peroxidation inhibition potential. Oxidative stress markers such as MDA, SOD, GSH, and CAT levels in cells further corroborated the research work. The study also indicated high concentrations of lysine (80.49 mg g-1 dry seeds) in AM-2, squalene (0.47% by weight) in AM-3, and 2,4-di-tert-butyl phenol (18.64% peak area) and myoinositol (79.07 mg g-1 dry seeds) in AM-5. This novel comparative metabolomic study successfully profiles the nutrient composition of amaranth cultivars and provides the opportunity for the development of nutraceuticals and natural antioxidants from this functional food.

Health Benefits of Bread Fortification: A Systematic Review of Clinical Trials according to the PRISMA Statement

Bread is among the most common foods for the world's population. Therefore, it can be fortified to eliminate deficiencies of nutrients or be a carrier of other substances with a nutritional or physiological effect, bringing health benefits to its consumers, thus impacting sustainable health. This systematic review aimed to analyze clinical studies on the effects of bread fortification on human health. The study followed the PRISMA guidelines for transparency and utilized databases Scopus, Embase, PubMed, and Web of Science to search clinical trials focused on the effects of bread fortification on human health over the entire last decade. The methodological quality of selected studies was assessed using the Jadad scale. As a result, twenty-six studies meet the inclusion criteria. Clinical trials have shown health benefits from consuming bread fortified with vitamins (B9, C, D2, D3), minerals (K, P, Ca, Mg, Fe, Zn, Cr, Se), fiber, proteins, and polyphenolic compounds. Conclusions reveal that mandatory fortification aligns with the sustainable development goals. Thus, collaborative partnerships are essential for successful implementation and accessibility, fostering public health advances and progress developing into sustainable health.

Effects of regular-fat and low-fat dairy consumption on daytime ambulatory blood pressure and other cardiometabolic risk factors: a randomized controlled feeding trial

BACKGROUND

The extent to which dairy products and their fat content influence cardiovascular health remains uncertain.

OBJECTIVE

This study aimed to assess how consumption of low-fat milk and regular-fat cheese enriched in γ-aminobutyric acid (GABA) influences daytime ambulatory blood pressure (BP) and other cardiometabolic risk factors.

METHODS

In this crossover controlled feeding study, 55 healthy men and women with high-normal daytime BP were randomly assigned to sequences of three 6-wk isoenergetic diets, each comprising 1) no dairy (control diet), 2) 3 daily servings of 1% fat milk, and 3) 1 daily serving of 31% fat cheddar cheese naturally enriched in GABA. Total proteins, carbohydrates, and fats were matched across all 3 diets. The additional 2% of energy from SFAs in the cheese diet was replaced by n-6 PUFAs in the other diets.

RESULTS

Comparison of postdiet ambulatory systolic BP revealed no difference (P = 0.34), which was also the case for ambulatory diastolic BP (P = 0.45). The cheese diet increased serum LDL-cholesterol concentrations compared with the control and milk diets (+5.8%, P = 0.006 and +7.0%, P = 0.0008, respectively) and increased LDL particle size compared with the milk diet (P = 0.02). HDL-cholesterol concentrations after the milk diet were lower than after the control diet (-4.1%; P = 0.009). The milk and cheese diets increased triglycerides compared with the control diet (+9.9%, P = 0.01 and +10.5%, P = 0.007, respectively). There was no significant difference between all diets for C-reactive protein concentrations and markers of glucose/insulin homeostasis.

CONCLUSIONS

These results suggest that short-term consumption of dairy products, whether low or regular in fat, has no overall effect on daytime ambulatory BP compared with a dairy-free diet. Other cardiometabolic risk factors may be differently modified according to the fat content of the dairy product. This trial was registered at clinicaltrials.gov as NCT02763930.

An Updated Review on Pharmaceutical Properties of Gamma-Aminobutyric Acid

Gamma-aminobutyric acid (Gaba) is a non-proteinogenic amino acid that is widely present in microorganisms, plants, and vertebrates. So far, Gaba is well known as a main inhibitory neurotransmitter in the central nervous system. Its physiological roles are related to the modulation of synaptic transmission, the promotion of neuronal development and relaxation, and the prevention of sleeplessness and depression. Besides, various pharmaceutical properties of Gaba on non-neuronal peripheral tissues and organs were also reported due to anti-hypertension, anti-diabetes, anti-cancer, antioxidant, anti-inflammation, anti-microbial, anti-allergy, hepato-protection, reno-protection, and intestinal protection. Therefore, Gaba may be considered as potential alternative therapeutics for prevention and treatment of various diseases. Accordingly, this updated review was mainly focused to describe the pharmaceutical properties of Gaba as well as emphasize its important role regarding human health.

Properties of Oils From Plantain Pseudostem Biotransformed Using Crude Local Enzyme Sources: A Comparison of Poultry Feed Oil

OBJECTIVES

Plantain Pseudostem (PPS) wastes were biotransformed by applying Simultaneous Saccharification and Fermentation (SSF) using excised snail digestive juice and yeast slurry, and their oil properties compared with oils from commercially sold poultry feeds (PF). Patents suggesting the inclusion of certain additives (US20090226558A1), spices (US5741508A), cysteamine (US4711897A), and dextrin (US6326051B1) in animal diets are regarded as expensive, thus, requiring cheaper and readily available sources of growth.

METHODS

The analysis of their free radical scavenging potentials was carried by spectrophotometry, while fatty acids, volatile fatty acids, essentials oils, and phytosterols were determined by chromatography.

RESULTS

After biotransformation, the melting point, specific gravity, acid, and peroxide values of the oils from SSF-PPS were significantly lower than those of PF, and showed elevations of C6:0- C18:1(trans-9) fatty acids, palmitic, stearic, γ-Linolenic, α-linolenic, behenic, and lignoceric acids. Camphene, β-phelandrene, eugenol, β-elemene, bicyclogermacrene, guaiol, tetradecanoic acid, and hexadecanoic acid levels decreased when PPS was biotransformed. Lactic (1575.75 mg/100g), acetic (1234.26 mg/100g), propionic (845.74 mg/100g), and n-butyric (68.56 mg/100g) acids were the predominant Volatile Fatty Acids (VFAs) in the SSF-PPS oils, which were higher than those found in the PF oil while PF oil contained higher campesterol, Stigmasterol, and 5-avesmasterol. The 2,2- azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS), 1,1-diphenyl-2- picrylhydrazyl (DPPH), superoxide, and nitric oxide radical scavenging potentials of PPS oil at high concentrations after biotransformation were equivalent to the standards and the PF oil.

CONCLUSION

This study has shown that biotransformation involving snail digestive juice and yeasts extensively improves the oil qualities of agricultural residues sufficient enough for poultry nutrition.

Influence of Sourdough Fermentation on Amino Acids Composition, Phenolic Profile, and Antioxidant Properties of Sorghum Biscuits

Biscuits were produced from sorghum with and without the addition of sourdough. The influence of sourdough fermentation on the amino acids composition, phenolic profile, and antioxidant properties of the biscuits were evaluated. Phenolic compounds of the biscuits were identified and quantified using gas chromatography/mass spectrometer. The total phenol contents (TPC), total flavonoid contents (TFC), ferric reducing antioxidant properties (FRAP), 2,2'-azinobis( 3-ethylbenzothiazoline-6-sulphonic) (ABTS) scavenging ability, 1,1-diphenyl-2-picryl-hydrazy (DPPH) scavenging ability, and nitric oxide (NO) scavenging ability of the biscuits were determined. Addition of sourdough increased the total essential amino acids, total non essential amino acids, hydrophobic, and aromatic amino acids contents of the biscuits. Essential amino acid index, biological value, and predicted protein efficiency were higher in biscuits with sourdough than in biscuits without sourdough. Six phenolic compounds were identified and quantified in the biscuits. Ferulic acid was the most prominent phenolic compound, followed by chlorogenic acid. TPC, TFC, FRAP, ABTS, DPPH, and NO scavenging abilities increased significantly with the addition of sourdough. Sorghum biscuits with sourdough could be useful in dietary interventions to prevent protein-energy malnutrition. Similarly, the presence of bioactive phenolic compounds and their antioxidant efficacy suggest health benefits in the management of oxidative stress and degenerative diseases.

Health benefits of fermented foods: microbiota and beyond

Fermented foods and beverages were among the first processed food products consumed by humans. The production of foods such as yogurt and cultured milk, wine and beer, sauerkraut and kimchi, and fermented sausage were initially valued because of their improved shelf life, safety, and organoleptic properties. It is increasingly understood that fermented foods can also have enhanced nutritional and functional properties due to transformation of substrates and formation of bioactive or bioavailable end-products. Many fermented foods also contain living microorganisms of which some are genetically similar to strains used as probiotics. Although only a limited number of clinical studies on fermented foods have been performed, there is evidence that these foods provide health benefits well-beyond the starting food materials.

Effect of potassium supplementation on vascular function: A meta-analysis of randomized controlled trials

BACKGROUND

Effects of potassium supplementation on vascular function remain conflicting. This meta-analysis aimed to summarized current literature to fill the gaps in knowledge.

METHODS

A literature search was performed on PubMed database through April, 2016. The measurements of vascular function included pulse wave velocity (PWV), augmentation index (AI), pulse pressure (PP), flow mediated dilatation (FMD), glycerol trinitrate responses (GTN), and intercellular cell adhesion molecule-1 (ICAM-1). Data were pooled as standardized mean difference (SMD) with 95% confidence intervals.

RESULTS

Seven randomized controlled trials examining 409 participants were included, with dosage of potassium ranging from 40 to 150mmol/day, and duration of intervention from 6days to 12months. Pooling results revealed a significant improvement in PP (SMD -0.280, 95% CI -0.493 to -0.067, p=0.010), but no improvement in PWV (SMD -0.342, 95% CI -1.123 to 0·440, p=0.391), AI (SMD -0.114, 95% CI -0.282 to 0.054, p=0.184), FMD (SMD 0·278, 95% CI -0.321 to 0.877, p=0.363), GTN (SMD -0.009, 95% CI -0.949 to 0.930, p=0.984), and ICAM-1 (SMD -0.238, 95% CI -0.720 to 0.244, p=0.333).

CONCLUSIONS

Potassium supplementation was associated with significant improvement of PP, rather than other measurements of vascular function. However, the small number of researches and wide variation of evidences make it difficult to make a definitive conclusion.